HBV genotype B is associated with better response to interferon therapy in HBeAg(+) chronic hepatitis than genotype C

MicroRNA-3145 as a potential therapeutic target for hepatitis B virus: inhibition of viral replication via downregulation of HBS and HBX

Current treatments for hepatitis B virus (HBV), such as interferons and nucleic acid analogs, have limitations due to side effects like depression and the development of drug-resistant mutants, highlighting the need for new therapeutic approaches. In this study, we identified microRNA-3145 (miR-3145) as a host-derived miRNA with antiviral activity that is upregulated in primary hepatocytes during HBV infection. The expression of its precursor, pri-miR-3145, increased in response to the the virus infection, and miR-3145 downregulated the hepatitis B virus S (HBS) antigen and hepatitis B virus X (HBX), thereby inhibiting viral replication. The binding site for miR-3145 was located in the HBV polymerase (pol) region, as experimentally confirmed. Moreover, overexpression of HBS and HBX induced pri-miR-3145 expression through endoplasmic reticulum stress. The expression of pri-miR-3145 showed a strong correlation with the Nance-Horan syndrome-like 1 (NHSL1) gene, as it is encoded within an intron of NHSL1, and higher NHSL1 expression in hepatocellular carcinoma patients with HBV infection was associated with better prognosis. These findings suggest that miR-3145-3p, along with small molecules targeting its binding sites, holds promise as a potential therapeutic candidate for HBV treatment.

IFN-treated macrophage-derived exosomes prevents HBV-HCC migration and invasion via regulating miR-106b-3p/PCGF3/PI3K/AKT signaling axis

BACKGROUND

Studies revealed that exosomes from IFN-α-treated liver non-parenchymal cells (IFN-exo) mediate antiviral activity. MiR-106b-3p has been shown to play a paradoxical role in disease progressing from different studies. However, its specific role in HBV-related hepatocellular carcinoma (HBV-HCC) and the underlying mechanism remains unclear.

METHOD

Huh7 cells transient transfected with plasmids of HBV-C2 and B3 were co-cultured with IFN-exo. Cell supernatants were collected to detect miR-106b-3p, HBsAg, HBeAg and HBV DNA levels. Cell proliferation, apoptosis, migration and invasion were analyzed. The putative targets of miR-106b-3p were identified by a dual-luciferase reporter system. The expression of PCGF3, migratory proteins(MMP2/9), and the PI3K/AKT signaling pathway-related proteins were assessed by western blot. The expression of PCGF3 mRNA was quantitative analyzed by using 52 pairs of paraffin-embedded tissues from HCC patients. siRNAs-PCGF3 were used to knocked-down PCGF3 expression.

RESULTS

The expression of miR-106b-3p was significantly higher in THP-1 cells and supernatants treated with IFN-exo than those untreated. Significantly increased expression of miR-106b-3p and decreased expression of HBsAg and HBV DNA were observed in Huh7-C2/B3 cells treated with IFN-exo. In addition, miR-106b-3p was directly target to PCGF3. Scratch healing assay and transwell assay showed that either IFN-exo or miRNA-106-3p over-expression, or siRNAs-PCGF3 inhibited migration and invasion of Huh7-C2/B3 cells, and subsequently resulted in suppression of p-AKT/AKT and p-PI3K/PI3K. Notably, the expression level of PCGF3 was significantly lower in HBeAg (+)-HCC tumor tissues than HBeAg (-)-HCC tumor.

CONCLUSION

IFN-α-induced macrophage-derived miR-106b-3p inhibits HBV replication, HBV- Huh7 cells migration and invasion via regulating PCGF3/PI3K/AKT signaling axis. miR-106b-3p and PCGF3 were potential biomarkers in the prevention and treatment of HBV-HCC.

Incidence and factors associated with hepatitis B surface antigen seroclearance in patients co-infected with HBV/HIV during antiretroviral therapy in Guangdong, China

BACKGROUND

Hepatitis B surface antigen (HBsAg) clearance is vital for a functional cure of hepatitis B virus (HBV) infection. However, the incidence and predictors of HBsAg seroclearance in patients co-infected with HBV and human immunodeficiency virus (HIV) remain largely unknown in Guangdong, China.

METHODS

Between 2009 and 2019, patients co-infected with HBV/HIV undergoing antiretroviral therapy (ART) in Guangzhou Eighth People's Hospital affiliated to Guangzhou Medical University were retrospectively reviewed with the endpoint on December 31, 2020. The incidence and risk factors for HBsAg seroclearance were evaluated using Kaplan-Meier and multivariate Cox regression analyses.

RESULTS

A total of 1550 HBV/HIV co-infected patients were included in the study, with the median age of 42 years and 86.0% (1333/1550) males. Further, 98.3% (1524/1550) received ART containing tenofovir disoproxil fumarate (TDF) plus lamivudine (3TC). HBV DNA was examined in 1283 cases at the last follow-up. Over the median 4.7 years of follow-up, 8.1% (126/1550) patients achieved HBsAg seroclearance, among whom 50.8% (64/126) obtained hepatitis B surface antibody, 28.1% (137/488) acquired hepatitis B e antigen seroconversion, and 95.9% (1231/1283) undetectable HBV DNA. Compared with patients who maintained HBsAg positive, cases achieving HBsAg seroclearance showed no differences in age, gender, CD4 + T cell count, alanine aminotransferase (ALT) level, or fibrosis status; however, they presented lower HBV DNA levels, lower HBsAg levels, and higher rates of HBV genotype B at the baseline. Multivariate analysis showed that baseline HBsAg <1500 cutoff index (COI) (adjusted hazard ratio [aHR], 2.74, 95% confidence interval [95% CI]: 1.48-5.09), ALT elevation >2 × upper limit of normal during the first six months after receiving ART (aHR, 2.96, 95% CI: 1.53-5.77), and HBV genotype B (aHR, 3.73, 95% CI: 1.46-9.59) were independent predictors for HBsAg seroclearance (all P <0.01).

CONCLUSIONS

Long-term TDF-containing ART has high anti-HBV efficacy including relatively high overall HBsAg seroclearance in HBV/HIV co-infected patients. Lower baseline HBsAg levels, HBV genotype B, and elevated ALT levels during the first six months of ART are potential predictors of HBsAg seroclearance.

HBsAg Loss as a Treatment Endpoint for Chronic HBV Infection: HBV Cure

Despite the availability of effective vaccines and antiviral therapy over the past two to three decades, chronic hepatitis B virus (HBV) infection remains a major global health threat as a leading cause of cirrhosis and liver cancer. Functional HBV cure defined as hepatitis B surface antigen (HBsAg) loss and undetectable serum HBV DNA is associated with improved clinical outcomes in patients with chronic HBV infection. However, spontaneous loss of HBsAg is rare and occurs in only 1% of all HBsAg-positive individuals annually. Furthermore, the rate of functional cure with currently available antiviral therapy is even lower, <1% patients on treatment per year. Nonetheless, HBsAg loss has become the new target or therapeutic endpoint for antiviral treatment. Recently, there has been much excitement surrounding the development of novel antiviral agents such as small interfering RNA (siRNA), core assembly modulators (CAMs), nucleic acid polymers (NAPs) among others, which may be used in combination with nucleos(t)ide analogs and possibly immunomodulatory therapies to achieve functional cure in a significant proportion of patients with chronic hepatitis B. Novel assays with improved sensitivity for detection of very low levels of HBsAg and to determine the source of HBsAg production will also be required to measure efficacy of newer antiviral treatments for HBV cure. In this narrative review, we will define HBV cure, discuss various sources of HBsAg production, evaluate rates of HBsAg loss with current and future antiviral agents, review clinical factors associated with spontaneous HBsAg loss, and explore clinical implications of functional cure.

Comparative Analysis of Serum Proteins Between Hepatitis B Virus Genotypes B and C Infection by DIA-Based Quantitative Proteomics

Purpose

In clinical practice, the clinicopathological profiles and outcomes of patients infected with hepatitis B virus (HBV) are different between genotypes B and C. However, little is known about the potential mechanism and differences in specific biological pathways associated with the different genotype. This study aimed to compare the serum protein profile between patients infected with HBV genotype B and those infected with HBV genotype C.

Patients and Methods

A total of 54 serum samples from patients with chronic HBV genotype B infection and those with chronic HBV genotype C infection, and healthy controls were used for the proteomic analysis (n = 18 samples in per group). Serum proteomic profiles were analyzed using data-independent acquisition (DIA)-based liquid chromatography-mass spectrometry to identify differentially expressed proteins (up- or downregulation of at least 1.5-fold) between serum samples from HBV patients infected with HBV genotype B and those infected with genotype C.

Results

We identified 1010 proteins, 53 of which were differentially expressed between the serum samples of the healthy controls and those of HBV genotype B infected patients, and 59 that were differentially expressed between the samples of the healthy controls and those of HBV genotype C infected patients. Furthermore, our results indicated that two proteins identified as being differentially expressed (VWF and C8B) have potential as biomarkers for distinguishing genotype B infected HBV patients from those infected with genotype C.

Conclusion

The results of our DIA-based quantitative proteomic analysis revealed that HBV genotypes B and C are associated with different molecular profiles and may provide fundamental information for further detailed investigations of the molecular mechanism underlying these differences.

Interferon and Hepatitis B: Current and Future Perspectives

Chronic hepatitis B virus (HBV) infection remains a major health burden worldwide for which there is still no effective curative treatment. Interferon (IFN) consists of a group of cytokines with antiviral activity and immunoregulatory and antitumor effects, that play crucial roles in both innate and adaptive immune responses. IFN-α and its pegylated form have been used for over thirty years to treat chronic hepatitis B (CHB) with advantages of finite treatment duration and sustained virologic response, however, the efficacy is limited and side effects are common. Here, we summarize the status and unique advantages of IFN therapy against CHB, review the mechanisms of IFN-α action and factors affecting IFN response, and discuss the possible improvement of IFN-based therapy and the rationale of combinations with other antiviral agents in seeking an HBV cure.

The Different Effects of Nucleotide and Nucleoside Analogues on the Prognosis of HBV-Related HCC After Curative Resection

BACKGROUND

Postoperative oral antiviral treatment with nucleoside or nucleotide analogues can suppress viral replication and reduce tumour recurrence for patients with hepatitis b virus-related hepatocellular carcinoma (HBV-related HCC) after curative resection. However, the superior antiviral treatment is still unclear. We conducted this study to investigate the different effects of nucleotide and nucleoside analogues on the prognosis of HBV-related HCC after curative resection.

METHODS

From February 2007 to February 2016, 487 consecutive patients with newly diagnosed HCC according to the Milan criteria who underwent R0 resection were enrolled according to the inclusion and exclusion criteria. According to their postoperative antiviral treatment, they were divided into the nucleotide group (NtA, n = 111) and the nucleoside group (NsA, n = 376).

RESULTS

The baseline characteristics, serologic parameters, tumour characteristics, and operative data of the 2 groups were comparable. Nucleotide analogue use significantly decreased HCC recurrence (P = 0.028) and HCC-related death (P = 0.004), with hazard ratios (HRs) of 0.685 (95% CI, 0.484 to 0.971, P = 0.033) and 0.507 (95% CI, 0.310 to 0.830, P = 0.004), respectively, in multivariate Cox analyses. After the study patients were stratified according to three variables, we found that nucleotide analogue use was significantly associated with increased disease-free and overall survival among patients with cirrhosis, HBeAg-negative patients, and patients with positive HBV-DNA.

CONCLUSIONS

In patients with HBV-related HCC, nucleotide analogues but not nucleoside analogues significantly reduced HCC recurrence and improved overall survival after R0 hepatic resection.

Investigational drugs with dual activity against HBV and HIV (Review)

Chronic hepatitis B (CHB) and acquired immunodeficiency syndrome (AIDS) are global public health problems that pose a significant health burden. Human immunodeficiency virus (HIV) and hepatitis B virus (HBV) coinfection is common, as these viruses have similar transmission routes, such as blood transmission, sexual transmission and mother-to-child transmission. Coinfection frequently leads to accelerated disease progression. For individuals coinfected with HIV/HBV, combination antiretroviral therapy containing dual anti-HBV drugs is recommended. Certain studies have also indicated the benefits of antiretroviral drugs with anti-HBV activity in patients with coinfection. A total of four Food and Drug Administration-approved HIV drugs also have anti-HBV activity; namely, emtricitabine, lamivudine, tenofovir disoproxil fumarate and tenofovir alafenamide, which are all nucleoside reverse transcriptase inhibitors. However, various issues, including drug resistance and side effects, limit their application. Therefore, it is necessary to develop more drugs with dual activity against HBV and HIV. The present review outlines the mechanisms, safety and efficacy of certain drugs that have been investigated for this purpose.

Impact of Hepatitis B Virus Genetic Variation, Integration, and Lymphotropism in Antiviral Treatment and Oncogenesis

Chronic Hepatitis B Virus (HBV) infection poses a significant global health burden. Although, effective treatment and vaccinations against HBV are available, challenges still exist, particularly in the development of curative therapies. The dynamic nature and unique features of HBV such as viral variants, integration of HBV DNA into host chromosomes, and extrahepatic reservoirs are considerations towards understanding the virus biology and developing improved anti-HBV treatments. In this review, we highlight the importance of these viral characteristics in the context of treatment and oncogenesis. Viral genotype and genetic variants can serve as important predictive factors for therapeutic response and outcomes in addition to oncogenic risk. HBV integration, particularly in coding genes, is implicated in the development of hepatocellular carcinoma. Furthermore, we will discuss emerging research that has identified various HBV nucleic acids and infection markers within extrahepatic sites (lymphoid cells). Intriguingly, the presence of hepatocellular carcinoma (HCC)-associated HBV variants and viral integration within the lymphoid cells may contribute towards the development of extrahepatic malignancies. Improved understanding of these HBV characteristics will enhance the development of a cure for chronic HBV infection.

Distribution of hepatitis B virus genotypes in the general population of Myanmar via nationwide study

Background

Hepatitis B virus (HBV) infections are a severe health concern worldwide. HBV is a DNA virus with a rapid rate of mutation. Based on heterogeneity of the nucleotide sequence, the HBV strains are divided into nine genotypes, each with a characteristic geographical distribution. Identifying and tracking alterations of HBV genotypes is important in epidemiological and transmission studies, and contributes to predicting the risk for development of severe liver disease and response to antiviral treatment. The present study was undertaken to detect HBV genotypes and sub-genotypes in the general population of different states and regions in Myanmar.

Methods

In 2015, a total of 5547 adults of the general population, residing in seven states, seven regions and the Nay Pyi Taw Union Territory, were screened for Hepatitis B Surface antigen (HBsAg) by the immunochromatographic test (ICT). Of the 353 HBsAg positive samples, the HBVDNA was identified using polymerase chain reactions (PCR) targeting the DNA sequences encoding the Pre-S region. A total of 153 PCR positive samples were subsequently subjected to genotyping by partial genome sequencing in both directions. The resulting sequences were then edited, aligned, and compared with reference sequences using the National Centre for Biotechnology Information (NCBI) web-based genotyping tool.

Results

Three HBV genotypes (HBV genotype B, genotype C and genotype D) were detected in Myanmar, of which genotype HBV genotype C (66.7%) was the most prevalent, followed by HBV genotype D (32%) and HBV genotype B (1.3%). Sub-genotyping revealed a total of 7 variants within the B, C and D genotypes: 2 (B4 and B5) in HBV genotype B, 3 (C1, C5 and C7) in HBV genotype C, and 2 (D3 and D6) in HBV genotype D.

Conclusion

HBV genotype C, sub-genotype C1 was predominantly distributed in all states and regions of Myanmar. This study is the first report on the nationwide distribution of HBV genotypes and sub-genotypes in Myanmar. We believe our findings will enable huge support for the hepatitis disease surveillance program, since HBV infection is one of the National Priority Diseases in Myanmar.

The characteristic of the synonymous codon usage and phylogenetic analysis of hepatitis B virus

Background

Hepatitis B virus (HBV) infection is a crucial medical issue worldwide. The dependence of HBV replication on host cell machineries and their co-evolutionary interactions prompt the codon usage pattern of viral genes to translation selection and mutation pressure.

Objective

The evolutionary characteristics of HBV and the natural selection effects of the human genome on the codon usage characteristics were analyzed to provide a basis for medication development for HBV infection.

Methods

The codon usage pattern of sequences from different HBV genotypes of our isolates and reference HBV genome sequences downloaded from the National Center for Biotechnology Information (NCBI) database were analyzed by computing the relative synonymous codon usage (RSCU), nucleotide content, codon adaptation index (CAI) and the effective number of codons (ENC).

Results

The highest ENC values were observed in the C genotypes, followed by the B genotypes. The ENC values indicated a weak codon usage bias (CUB) in HBV genome. The number of codons differentially used between the three genotypes was markedly higher than that of similarly used codons. High CAI values indicated a good adaptability of HBV to its host. The ENC plot indicated the occurrence of mutational pressure in the three genotypes. The mean Ka/Ks ratios in the three genotypes were lower than 1, which indicated a negative selection pressure. The CAI and GC3% plot indicated the existence of CUB in the HBV genome.

Conclusions

Nucleotide composition, mutation bias, negative selection and mutational pressure are key factors influencing the CUB and phylogenetic diversity in HBV genotypes. The data provided here could be useful for developing drugs for HBV infection.

Electronic supplementary material

The online version of this article (10.1007/s13258-020-00932-w) contains supplementary material, which is available to authorized users.

The response of hepatitis B virus genotype to interferon is associated with a mutation in the interferon-stimulated response element

Genetic variation and genotype of Hepatitis B virus (HBV) are related to the efficiency of interferon alpha (IFN-α)-based antiviral therapy. However, the correlation of variation in interferon-stimulated response element (ISRE) and HBV genotype response to IFN-α therapy remains elusive.Differences of ISRE between genotype B and C HBV were explored using the HBV sequences retrieved from GenBank, and further investigated by ISRE region cloning and sequencing from 60 clinical samples post-IFN-α therapy. Additionally, ISRE mutants were constructed and their relation to responsiveness of IFN-α was evaluated by real-time PCR and Southern blot analysis.ISRE pattern between genotype B and C were found based on both clinical sample sequencing and full-length sequence alignment. The primary difference is the fourth base within the ISRE region, with T and C for genotype B and C, respectively. HBV with genotype C-type ISRE had a higher replicative capability as compared to HBV with genotype B-type ISRE after IFN-α treatment in huh7 cells. CONCLUSION:: Preference of ISRE between genotype B and C HBV are distinct. Single nucleotide difference (C to T) within the HBV ISRE region may link to the efficacy of IFN-α therapy to genotype B and C HBV. Therefore, this study provides a clue for the determination of IFN-α therapy response to HBV treatment.

Genotype Matters in Patients with Acute-on-chronic Liver Failure Due to Reactivation of Chronic Hepatitis B

Background

Acute-on-chronic liver failure (ACLF) can be caused by reactivation of chronic hepatitis B virus (HBV) infection (HBV-ACLF). It’s unclear whether HBV genotypes affect the clinical and therapeutical outcomes of patients with HBV-ACLF. This study was to investigate the short-term antiviral response and overall survival in HBV-ACLF patients treated by tenofovir or entecavir.

Methods

Seventy-three consecutive patients with HBV-ACLF were stratified into genotype B group (n = 33) and C group (n = 40). They were prospectively followed-up.

Results

At 2 weeks, the genotype B group had significantly lower HBV-DNA load (P = 0.005), greater HBV-DNA decline (P = 0.026), higher proportion of patients with HBV-DNA < 500 IU/ml (P = 0.007), improved Child-Turcotte-Pugh (CTP; P = 0.032) and model for end-stage liver disease (MELD; P = 0.039) scores compared to the genotype C group. At three months, survivors in both groups had undetectable HBV-DNA loads, comparable CTP (P = 0.850) and MELD (P = 0.861) scores; the genotype C group had markedly lower overall survival rate than the B group (P = 0.013). The genotype (hazard ratio [HR]: 2.138; 95% confidence interval [CI]: 1.034–4.143; P = 0.041), MELD score (HR:1.664, 95%CI: 1.077–2.571; P = 0.022) and HBV-DNA decline (HR: 0.225, 95% CI: 0.067–0.758; P = 0.016) at 2 weeks were significantly associated with mortality at 3 months. No severe adverse event was noted.

Conclusions

Genotype B was associated with better short-term antiviral response and clinical outcome compared to genotype C in patients with HBV-ACLF.

Chinese Herbal Medicine Combined with Entecavir for HBeAg Positive Chronic Hepatitis B: Study Protocol for a Multi-Center, Double-Blind Randomized-Controlled Trial

BACKGROUND

The domestic prevalence of chronic hepatitis B (CHB) in China is 7.18% in 2006, imposing great societal healthcare burdens. Nucleot(s)ide analogues (NUCs) anti-hepatitis B virus (HBV) therapies are widely applied despite the relatively low rate of seroconversion and high risk of drug-resistant mutation. More effective treatments for CHB deserve further explorations. Combined therapy of NUCs plus Chinese herbal medicine (CHM) is widely accepted in China, which is recognized as a prospective alternative approach. The study was primarily designed to confirm the hypothesis that Tiaogan-Yipi Granule (, TGYP) or Tiaogan-Jianpi-Jiedu Granule (, TGJPJD) plus entecavir tablet (ETV) was superior over ETV monotherapy in enhancing HBeAg loss rate.

METHODS

The study was a nationwide, large-scale, multi-center, double-blind, randomized, placebo-controlled trial with a designed duration of 108 weeks. A total of 16 hospitals and 596 eligible Chinese HBeAg positive CHB patients were enrolled from November 2012 to September 2013 and randomly allocated into 2 groups in 1:1 ratio via central randomization system: experimental group (EG) and control group (CG). Subjects in EG received CM formulae (TGYP or TGJPJD, 50 g per dose, twice daily) plus ETV tablet (or ETV placebo) 0.5 mg per day in the first 24 weeks (stage 1), and CHM granule plus ETV tablet (0.5 mg per day) from week 25 to 108 (stage 2). Subjects in CG received CHM Granule placebo plus ETV tablet (0.5 mg per day) for 108 weeks throughout the trial. The assessments of primary outcomes (HBV serum markers and HBV-DNA) were conducted by a third-party College of American Pathologists (CAP) qualified laboratory. Adverse effects were observed in the hospitals of recruitment.

DISCUSSION

The study was designed to compare the curative effect of CM plus ETV and ETV monotherapy in respect of HBeAg loss, which is recognized by the European Association for the Study of the Liver as "a valuable endpoint". We believe this trial could provide a reliable status for patients' "journey" towards durable responses after treatment discontinuation. The trial was registered before recruitment on Chinese Clinical trial registry (No. ChiCTR-TRC-12002784, Version 1.0, 2015/12/23).

Detection of HBV Genotype C in Hepatocellular Carcinoma Patients from North East India: a Brief Report

Background and Objectives: Newer genotypes of HBV have been reported from India. This study was aimed to determine the circulating genotypes of HBV in hepatocellular carcinoma patients from three different geographical locations of India. Methods: 141 HBV related HCC cases were included from three different hospitals across the country. Genotyping of HBV was performed by PCR using type specific primers specially designed in 70 cases. Samples of interest were confirmed by direct sequencing of the precore/core region of HBV genome. Results: Genotypes could be detected in 40 (57.14%) out of the 70 HBV DNA positive HCC cases by type specific primers. HBV genotype D was documented in 20 (50%), genotype A in 10 (25.0%) and genotype C in 10 (25.0%) of these HCC cases. Genotype C of HBV was detected only in the samples from North East India. No significant difference was observed for the biochemical profile. Conclusion: Although Genotype D is the major HBV genotype in India followed by A, detection of HBV genotypes C in HCC patients indicates a changing epidemiology of the virus in India that may require region based management of the virus.

Treatment strategies according to genotype for chronic hepatitis B in children

This review article was requested by editor-in-chief of this journal as 'pediatric CHB treatment' for the upcoming special issue. The main objective of chronic hepatitis B (CHB) treatment is diminishing the risk of complications related to chronic liver disease. In Asia, there are already some reports about hepatocellular carcinoma (HCC) in hepatitis B virus (HBV) infected children. The key points of treatment in children with CHB infections are selection of which patients to treat and conformation of the optimal therapy time that would reduce viral resistance. The choice of therapy is determined by the district (Western/Eastern), HBV genotype, medical accessibility, and economic state of the country. Newly developed nucleos(t)ide analogues (NAs) are potent in children with CHB. However, to improve therapeutic efficacy, physicians are recommended to follow treatment guidelines and determine the specific genotype in the CHB patient. In this article, the treatment of pediatric CHB is reviewed according to differences in genotype.

Distribution and clinical significance of hepatitis B virus genotypes in Pakistan

Background

Hepatitis B virus (HBV) genotype and its role in disease progression and patients’ response to antiviral treatment, is not well studied in Pakistan. This comprehensive study was aimed to determine the distribution of HBV genotypes in Pakistan and their possible association with phases of HBV infection.

Methods

A total of 840 HBsAg positive samples was collected and tested for HBV DNA quantity. Samples below 100 IU/ml were excluded from the study. A total of 715 samples representing all the six parts of the country were genotyped by type specific primer PCR method. Clinical data of only 384 patients was compared as the remaining 332 were either receiving antiviral treatment or their infection phase was not confirmed.

Results

Genotype D was found in 509 samples (71.2 %), genotype A in 55 samples (7.7 %) and mixed infection with genotypes A and D in 124 samples (17.3 %). Genotypes B, C and E were identified in less than 1 % of the total samples. Genotype A, D and their mixture (A + D) were compared for severity of HBV infection. Significant differences were not found in distribution of HBV genotypes among different disease stages.

Conclusion

HBV genotype D was the predominant infection in all study areas of Pakistan followed by mixed genotypes infection (A + D) whereas genotype A has 10 times lower prevalence than genotype D. Genotypes B, C, E and F altogether make only 1.5 % of the prevalence. Genotype do not appears to show the severity of liver disease.

Stronger enhancer II/core promoter activities of hepatitis B virus isolates of B2 subgenotype than those of C2 subgenotype

Hepatitis B virus (HBV) genotype C causes prolonged chronic infection and increased risk for liver cancer than genotype B. Our previous work revealed lower replication capacity of wild-type genotype C2 than B2 isolates. HBV DNA replication is driven by pregenomic RNA, which is controlled by core promoter (CP) and further augmented by enhancer I (ENI) and enhancer II (ENII). DNA fragments covering these regulatory elements were amplified from B2 and C2 isolates to generate luciferase reporter constructs. As ENII is fully embedded in CP, we inserted HBV DNA fragments in the sense orientation to determine their combined activities, and in the antisense orientation to measure enhancer activities alone. Genotype B2 isolates displayed higher ENI+ENII+CP, ENII+CP, and ENII activities, but not ENI or ENI+ENII activity, than C2 isolates. The higher ENII+CP activity was partly attributable to 4 positions displaying genotype-specific variability. Exchanging CP region was sufficient to revert the replication phenotypes of several B2 and C2 clones tested. These results suggest that a weaker ENII and/or CP at least partly accounts for the lower replication capacities of wild-type C2 isolates, which could drive the subsequent acquisition of CP mutations. Such mutations increase genome replication and are implicated in liver cancer development.

An Observational, Multicenter, Cohort Study Evaluating the Antiviral Efficacy and Safety in Korean Patients With Chronic Hepatitis B Receiving Pegylated Interferon-alpha 2a (Pegasys): TRACES Study

Currently, limited data are available regarding the efficacy and safety of pegylated interferon alpha-2a (PEG-IFN α-2a) in Korean patients with chronic hepatitis B (CHB), in whom hepatitis B virus (HBV) genotype C is the most common type.We collected data from 439 patients (HBeAg positive, n = 349; HBeAg negative, n = 90) with CHB who were treated with PEG-IFN α-2a as a first-line therapy from 18 institutions. Treatment responses at the end of treatment (ET) and at 6 months posttreatment (PT6) were compared between the patients who were treated for 24 weeks versus 48 weeks, and adverse events (AEs) were evaluated.In HBeAg-positive patients, those who received PEG-IFN α-2a for 48 weeks showed significantly higher HBV DNA suppression (HBV DNA < 2000 IU/mL) than those who were treated for 24 weeks (48 weeks vs 24 weeks; at ET, 44.4% vs 36.7%, P = 0.035; at PT6, 35.9% vs 13.3%, P = 0.035). The HBeAg seroconversion rate at ET was 18.1% in 48-week treatment group, which is significantly higher than the 2.2% (P < 0.001) that was seen in 24-week treatment group. This finding also continued at PT6 (29.0% vs 10.0%, P < 0.001). Following 48 weeks of treatment in HBeAg-negative patients, HBV DNA suppression at ET was higher than in HBeAg-positive patients (87.8% vs 44.4%). AEs were typical of those associated with PEG-IFN α-2a.In naïve Korean HBeAg-positive CHB patients treated with PEG-IFN α-2a, higher rates of HBV DNA suppression and HBeAg seroconversion were achieved in the 48-week treatment group than in the 24-week treatment group without additional risk of AEs.

Circulating human cytomegalovirus-encoded HCMV-miR-US4-1 as an indicator for predicting the efficacy of IFNα treatment in chronic hepatitis B patients

The efficacy of interferon α (IFNα) therapy for chronic hepatitis B (CHB) patients is about 40% and often associates with adverse side-effects, thus identification of an easy accessible biomarker that can predict the outcome of IFNα treatment for individual CHB patients would be greatly helpful. Recent reports by us and others show that microRNAs encoded by human cytomegalovirus (HCMV) were readily detected in human serum and can interfere with lymphocyte responses required by IFNα therapeutic effect. We thus postulate that differential expression profile of serum HCMV miRNAs in CHB patients may serve as indicator to predict the efficacy of IFNα treatment for CHB patients. Blood was drawn from 56 individual CHB patients prior to IFNα treatment. By quantifying 13 HCMV miRNAs in serum samples, we found that the levels of HCMV-miR-US4-1 and HCMV-miR-UL-148D were significantly higher in IFNα-responsive group than in IFNα-non-responsive group. In a prospective study of 96 new CHB patients, serum level of HCMV-miR-US4-1 alone classified those who were and were not responsive to IFN-α treatment with correct rate of 84.00% and 71.74%, respectively. In conclusion, our results demonstrate that serum HCMV-miR-US4-1 can serve as a novel biomarker for predicting the outcome of IFNα treatment in CHB patients.

Epidemiology study of HBV genotypes and antiviral drug resistance in multi-ethnic regions from Western China

Hepatitis B virus (HBV) infection is a critical global health issue and moderately epidemic in Western China, but HBV molecular epidemiology characteristics are still limited. We conducted this study to investigate HBV genotypes and antiviral resistant mutations in this multi-ethnic area. A total of 1316 HBV patients were recruited from four ethnic groups from 2011 to 2013. Genotypes and resistant mutations were determined by Sanger sequencing. Four genotypes (B, C, D and C/D) were identified. Genotype B and C were common in Han population, while genotype D was predominant in Uygurs. Genotype C was the major genotype in both Tibetans and Yis, and recombinant C/D was found in Tibetans only. Lamivudine resistance was common in all populations, especially in Hans with prevalence of 42.8%. Entecavir resistance was barely observed regardless of ethnicity. Genotype C isolates had higher rates of rtA181T/V than genotype B (13.5% vs. 5.1%, P < 0.001), in accordance with higher prevalence of resistance to adefovir (20.0% vs. 9.5%, P < 0.001). While incidence of resistant mutations to other drugs and clinical factors showed no difference among different genotypes. HBV genotypes and resistance-conferring mutations had different geographic and demographic distributions in Western China, which provided molecular epidemiology data for clinical management.

Hepatitis B virus spliced variants are associated with an impaired response to interferon therapy

During hepatitis B virus (HBV) replication, spliced HBV genomes and splice-generated proteins have been widely described, however, their biological and clinical significance remains to be defined. Here, an elevation of the proportion of HBV spliced variants in the sera of patients with chronic hepatitis B (CHB) is shown to correlate with an impaired respond to interferon-α (IFN-α) therapy. Transfection of the constructs encoding the three most dominant species of spliced variants into cells or ectopic expression of the two major spliced protein including HBSP and N-terminal-truncated viral polymerase protein result in strong suppression of IFN-α signaling transduction, while mutation of the major splicing-related sites of HBV attenuates the viral anti-IFN activities in both cell and mouse models. These results have associated the productions of HBV spliced variants with the failure response to IFN therapy and illuminate a novel mechanism where spliced viral products are employed to resist IFN-mediated host defense.

Hepatitis B virus genotype, mutations, human leukocyte antigen polymorphisms and their interactions in hepatocellular carcinoma: a multi-centre case-control study

Three genome-wide association studies (GWAS) have been conducted on the genetic susceptibility of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), two of which consistently identified tagging single nucleotide polymorphisms (SNPs) around HLA-DQ/DR. In contrast, large multi-centre association studies between HBV genotype, mutations and the risk of HCC are relatively rare, and their interactions with host variants are even less. We performed a multi-centre study of 1,507 HBV-related HCC cases and 1,560 HBV persistent carriers as controls to evaluate the effects of HBV genotype, mutations, GWAS-identified HLA-DQ/DR SNPs (rs9272105 and rs9275319) and their interactions on HCC risk. We found HBV genotype C was more frequent in HBV-related HCC. And 11 HBV hotspot mutations were independently and significantly associated with HCC risk. We also detected significant interactions of rs9272105 with both the HBV genotype and mutations. Through stepwise regression analysis, HBV genotype, the 11 mutations, HLA-DQ/DR SNPs, and the interaction of rs9272105 with mutation A1752G were all entered into the HCC prediction model, and the area under the curve for the panel including the HLA-DQ/DR SNPs, HBV genotype and mutations was 0.840. The HBV genotype, the mutations and the HLA-DQ/DR SNPs may serve as biomarkers for the surveillance of HBV persistent carriers.

Doubly Spliced RNA of Hepatitis B Virus Suppresses Viral Transcription via TATA-Binding Protein and Induces Stress Granule Assembly

The risk of liver cancer in patients infected with the hepatitis B virus (HBV) and their clinical response to interferon alpha therapy vary based on the HBV genotype. The mechanisms underlying these differences in HBV pathogenesis remain unclear. In HepG2 cells transfected with a mutant HBV(G2335A) expression plasmid that does not transcribe the 2.2-kb doubly spliced RNA (2.2DS-RNA) expressed by wild-type HBV genotype A, the level of HBV pregenomic RNA (pgRNA) was higher than that in cells transfected with an HBV genotype A expression plasmid. By using cotransfection with HBV genotype D and 2.2DS-RNA expression plasmids, we found that a reduction of pgRNA was observed in the cells even in the presence of small amounts of the 2.2DS-RNA plasmid. Moreover, ectopic expression of 2.2DS-RNA in the HBV-producing cell line 1.3ES2 reduced the expression of pgRNA. Further analysis showed that exogenously transcribed 2.2DS-RNA inhibited a reconstituted transcription in vitro. In Huh7 cells ectopically expressing 2.2DS-RNA, RNA immunoprecipitation revealed that 2.2DS-RNA interacted with the TATA-binding protein (TBP) and that nucleotides 432 to 832 of 2.2DS-RNA were required for efficient TBP binding. Immunofluorescence experiments showed that 2.2DS-RNA colocalized with cytoplasmic TBP and the stress granule components, G3BP and poly(A)-binding protein 1 (PABP1), in Huh7 cells. In conclusion, our study reveals that 2.2DS-RNA acts as a repressor of HBV transcription through an interaction with TBP that induces stress granule formation. The expression of 2.2DS-RNA may be one of the viral factors involved in viral replication, which may underlie differences in clinical outcomes of liver disease and responses to interferon alpha therapy between patients infected with different HBV genotypes.

IMPORTANCE

Patients infected with certain genotypes of HBV have a lower risk of hepatocellular carcinoma and exhibit a more favorable response to antiviral therapy than patients infected with other HBV genotypes. Using cultured human hepatoma cells as a model of HBV infection, we found that the expression of 2.2DS-RNA caused a decrease in HBV replication. In cultured cells, the ectopic expression of 2.2DS-RNA obviously reduced the intracellular levels of HBV mRNAs. Our analysis of the 2.2DS-RNA-mediated suppression of viral RNA expression showed that 2.2DS-RNA inhibited transcription via binding to the TATA-binding protein and stress granule proteins. Our findings suggest that the 2.2DS-RNA acts as a suppressive noncoding RNA that modulates HBV replication, which may in turn influence the development of chronic hepatitis B.

Current and future directions for treating hepatitis B virus infection

Hepatitis B virus (HBV) persistently infects approximately 350 million people, and approximately 600000 liver-related deaths are observed per year worldwide. HBV infection is also one of the major risk factors for hepatocellular carcinoma (HCC). The persistence of serum hepatitis B e antigen (HBeAg) and high level of serum HBV DNA are thought to reflect a high HBV replication status in hepatocytes, causing cirrhosis, HCC and liver-related deaths. It has been reported that antiviral therapy, such as peginterferon and nucleos(t)ide analogues (NUCs), could suppress liver-related death by inhibiting the HBV DNA levels and inducing seroconversion from HBeAg to antibody to HBe antigen. Currently, peginterferon is widely used, but there are also several disadvantages in the use of peginterferon, such as various adverse events, the administration route and duration. It is difficult to predict the effects of treatment and interferon is contraindicated for the patients with advanced fibrosis of the liver and cirrhosis. With respect to NUCs, entecavir and tenofovir disoproxil fumarate are current the first-choice drugs. NUCs can be administered orally, and their anti-viral effects are stronger than that of peginterferon. However, because cessation of NUC administration leads to high levels of viral replication and causes severe hepatitis, they must be administered for a long time. On the other hand, the use of both interferon and NUCs cannot eliminate covalently closed circular DNA of HBV. In this review, we evaluate the natural course of chronic HBV infection and then provide an outline of these representative drugs, such as peginterferon, entecavir and tenofovir disoproxil fumarate.

Hepatitis B virus genotypes and variants

At least 10 hepatitis B virus (HBV) genotypes (A to J) with distinct geographic distributions and several HBV mutants, including precore/core promoter mutations and pre-S/S deletion mutations, have been recognized to be not only predictive of liver disease progression but also associated with response to antiviral therapy. HBV genotype-specific pathogenesis may contribute to heterogeneous clinical outcomes in chronic hepatitis B patients across the world. For example, patients with HBV genotypes C and D infection have a lower rate of spontaneous HBeAg seroconversion. In addition, HBV genotypes C and D have a higher frequency of core promoter and pre-S mutations than genotypes A and B. Genotypes C and D also carry a higher lifetime risk of cirrhosis and HCC development than genotypes A and B. Core promoter and pre-S mutations also correlate with an increased risk of hepatocellular carcinoma (HCC). Therapeutically, genotypes A and B patients have a better response to interferon-based therapy than genotypes C and D patients, but the response to nucleos(t)ide analogs is comparable across different HBV genotypes. In conclusion, HBV genotypes and variants may serve as viral genetic markers to predict disease progression as well as help practicing physicians optimize individualized antiviral therapy in clinical practice.

A deep-sequencing method detects drug-resistant mutations in the hepatitis B virus in Indonesians

OBJECTIVE

The long-term administration of a nucleos(t)ide analogue (NA) for the treatment of chronic hepatitis B may encourage the emergence of viral mutations associated with drug resistance. Minor populations of viruses may exist before treatment, but are difficult to detect because of technological limitations. Identifying minor viral quasispecies should be useful in the clinical management of hepatitis B virus (HBV) infection.

METHODS

Six treatment-naïve Indonesian patients with chronic HBV infection participated in this study. The polymerase region of the HBV genome, including regions with known drug-resistant mutations, was subjected to capillary sequencing and MiSeq sequencing (Illumina). Mutations were analyzed with Genomics Workbench software version 6.0.1 (CLC bio).

RESULTS

The mean mapping reads for the six samples was 745,654, and the mean number of amplified fragments ranged from 17,926 to 25,336 DNA reads. Several known drug-resistant mutations in the reverse transcriptase region were identified in all patients, although the frequencies were low (0.12-1.06%). The proportions of the total number of reads containing mutations I169L/M, S202R, M204I/L or N236S were >1.0%.

CONCLUSION

Several known NA-resistant mutations were detected in treatment-naïve patients in Indonesia using deep sequencing. Careful management of such patients is essential to prevent drug-resistant mutations from spreading to other patients.

Hepatitis B virus coinfection in human immunodeficiency virus-infected patients: A review

Hepatitis B virus (HBV) infection is a leading cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma worldwide. Due to the shared modes of transmission, coinfection with HBV and human immunodeficiency virus (HIV) is not uncommon. It is estimated that 10% of HIV-infected patients worldwide are coinfected with HBV. In areas where an HBV vaccination program is implemented, the HBV seroprevalence has declined significantly. In HIV/HBV-coinfected patients, HBV coinfection accelerates immunologic and clinical progression of HIV infection and increases the risk of hepatotoxicity when combination antiretroviral therapy (cART) is initiated, while HIV infection increases the risk of hepatitis events, cirrhosis, and end-stage liver disease related to chronic HBV infection. With the advances in antiviral therapy, concurrent, successful long-term suppression of HIV and HBV replication can be achieved in the cART era. To reduce the disease burden of HBV infection among HIV-infected patients, adoption of safe sex practices, avoidance of sharing needles and diluent, HBV vaccination and use of cART containing tenofovir disoproxil fumarate plus emtricitabine or lamivudine are the most effective approaches. However, due to HIV-related immunosuppression, using increased doses of HBV vaccine and novel approaches to HBV vaccination are needed to improve the immunogenicity of HBV vaccine among HIV-infected patients.

Management of chronic hepatitis B infection: current treatment guidelines, challenges, and new developments

Chronic hepatitis B (CHB) virus infection is a global public health problem, affecting more than 400 million people worldwide. The clinical spectrum is wide, ranging from a subclinical inactive carrier state, to progressive chronic hepatitis, cirrhosis, decompensation, and hepatocellular carcinoma. However, complications of hepatitis B virus (HBV)-related chronic liver disease may be reduced by viral suppression. Current international guidelines recommend first-line treatment of CHB infection with pegylated interferon, entecavir, or tenofovir, but the optimal treatment for an individual patient is controversial. The indications for treatment are contentious, and increasing evidence suggests that HBV genotyping, as well as serial on-treatment measurements of hepatitis B surface antigen and HBV DNA kinetics should be used to predict antiviral treatment response. The likelihood of achieving a sustained virological response is also increased by extending treatment duration, and using combination therapy. Hence the paradigm for treatment of CHB is constantly evolving. This article summarizes the different indications for treatment, and systematically reviews the evidence for the efficacy of various antiviral agents. It further discusses the shortcomings of current guidelines, use of rescue therapy in drug-resistant strains of HBV, and highlights the promising clinical trials for emerging therapies in the pipeline. This concise overview presents an updated practical approach to guide the clinical management of CHB.

Hepatitis B and C in African Americans: current status and continued challenges

Viral hepatitis remains a public health concern in the United States, resulting in excess morbidity and mortality for the individual and representing a burden to societies as evidenced by billions of dollars in health care expenditures. As with many chronic diseases, race and ethnicity influence various aspects of disease pathogenesis, including mechanisms of persistence, disease progression, disease sequelae, and response to therapy. For hepatitis B and C infections, African Americans disproportionately bear a large burden of disease in the United States. The role and importance of African American race, however, have been less well-characterized in the literature among the population of viral hepatitis-infected individuals. The differences in epidemiology, manifestations of liver disease, response to therapy, and differential trends in liver transplantation in African Americans compared with other racial and ethnic groups deserve special attention. This review will address the current status of hepatitis B and C infection in African Americans in the United States and identify some of the remaining challenges in diagnosis, characterization of natural history, and treatment. For the purposes of this review, the terms African American and black will be used interchangeably throughout the text.

What physicians should know about the management of chronic hepatitis B in children: East side story

Understanding the natural course of chronic hepatitis B virus (HBV) infection is very important for the management and treatment of chronic hepatitis B in children. Based on treatment guidelines, the management of HBV carriers and treatment of active hepatitis have been advancing and resulted in increased survival, as well as decreased risks of complications such as liver cirrhosis and hepatocellular carcinoma. Development of a continuing medical education (CME) program for primary physicians becomes an important responsibility of pediatric hepatologists. CME could prevent misdiagnosis and unnecessary treatment that could lead to liver complications or antiviral resistance. In addition, education of patients and their parents is necessary to achieve better therapeutic outcomes.

Antiviral therapies: focus on hepatitis B reverse transcriptase

Hepatitis B virus (HBV) is the etiologic agent of mankind's most serious liver disease. While the availability of a vaccine has reduced the number of new HBV infections, the vaccine does not benefit the approximately 350 million people already chronically infected by the virus. Most of the drugs approved by the FDA for the treatment of hepatitis B target the reverse transcriptase (RT or P gene product) and are nucleoside RT inhibitors (NRTIs) that suppress viral replication. However, prolonged monotherapies directed against a single target result in the emergence of viral resistance. HBV genotypic differences affect NRTI resistance, and because the reading frames of the S (surface antigen) and P genes partially overlap, genomic differences that affect the surface of the virus may also alter the viral polymerase sequence, function and drug susceptibility. The scope of this review is to assess the effects of HBV genotypic variation on the development of drug resistance to NRTIs. Some RT residues that vary among different genotypes are in the vicinity of residues that mutate and give rise to NRTI resistance. Interactions between these amino acids can help explain the effect of HBV genotype on the development of NRTI resistance during antiviral therapies, and might help in the design of improved therapeutic strategies.

Systematic review of the literature on comparative effectiveness of antiviral treatments for chronic hepatitis B infection

OBJECTIVES

To evaluate the comparative effectiveness of antiviral drugs in adults with chronic hepatitis B monoinfection for evidence-based decision-making.

METHODS

A systematic review of randomized controlled clinical trials (RCTs) published in English. Results after interferon and nucleos(t)ides analog therapies were synthesized with random-effects meta-analyses and number needed to treat (NNT).

RESULTS

Despite sustained improvements in selected biomarkers, no one drug regimen improved all intermediate outcomes. In 16 underpowered RCTs, drug treatments did not reduce mortality, liver cancer, or cirrhosis. Sustained HBV DNA clearance was achieved in one patient when two were treated with adefovir (NNT from 1 RCT=2 95%CI 1;2) or interferon alpha-2b (NNT from 2 RCTs=2 95%CI 2;4), 13 with lamivudine (NNT from 1 RCT=13 95%CI 7;1000), and 11 with peginterferon alpha-2a vs. lamivudine (NNT from 1 RCT=11 95%CI 7;25). Sustained HBeAg seroconversion was achieved in one patient when eight were treated with interferon alpha-2b (NNT from 2 RCTs=8 95%CI 5;33) or 10--with peginterferon alpha-2b vs. interferon alpha-2b (NNT from 1 RCT=10 95%CI 5;1000). Greater benefits and safety after entecavir vs. lamivudine or pegylated interferon alpha-2b vs. interferon alpha-2b require future investigation of clinical outcomes. Adverse events were common and more frequent after interferon. Treatment utilization for adverse effects is unknown.

CONCLUSIONS

Individual clinical decisions should rely on comparative effectiveness and absolute rates of intermediate outcomes and adverse events. Future research should clarify the relationship of intermediate and clinical outcomes and cost-effectiveness of drugs for evidence-based policy and clinical decisions.

An overview of treatment response rates to various anti-viral drugs in Pakistani hepatitis B virus infected patients

Hepatitis B virus (HBV) is one of the leading health problem with up to 350 million affected people worldwide including 4.5 million only in Pakistan. It has mortality rate of 0.5 to 1.2 million per year worldwide. Pakistan lies in the endemic region with 3-5% HBV carrier rate in the country. The present article reviews the literature on the treatment response of HBV prevalent in Pakistani population. The average treatment response of Lamivudine and interferon-α is 25.81% and 47.95%, respectively. Peg-Interferon was shown to be not effective against the HBV/HCV (hepatitis C virus)/HDV (hepatitis Delta virus) co-infection. The present study reveals that interferon-α is the most effective therapy available for HBV infection prevalent in Pakistani population. Genotype C & D are the most common HBV genotypes in Pakistan and are associated with increased severity and less response to interferon therapy. This poses a great challenge for physicians and researchers and further studies are needed to describe the outcome of the current therapies recommended against HBV infection in Pakistani population.

Management and treatment of hepatitis B virus in patients with HIV infection: A practical guide for health care professionals

The management and treatment of HIV and hepatitis B virus (HBV)-coinfected patients present specific challenges for clinicians. The morbidity and mortality related to these concomitant infections are growing concerns, while the use of antiviral drugs effective against both viruses complicates therapeutic decision making. The present document provides guidelines for physicians regarding care and treatment of patients coinfected with HIV and HBV. Primary prevention of HBV in HIV-positive patients is achieved through appropriate vaccination schedules. Follow-up before treatment of HBV may include liver biopsy, screening for hepatocellular carcinoma and testing for esophageal varicies in cases of cirrhosis. In HBV-infected patients requiring treatment, recommendations regarding initiation, duration and choice of first-line drugs are made. Finally, in the case of resistance, appropriate alternative therapies are necessary.

The Role of Interferon in Hepatitis B Therapy

Despite the introduction of new nucleos(t)ide analogues in recent years, peginterferon is still recommended as a potential first-line treatment option by current practice guidelines for the management of chronic hepatitis B. Peginterferon offers the advantage of higher sustained off-treatment response rates compared to nucleos(t)ide analogues because of its immunomodulatory effects. Sustained transition to the inactive hepatitis B surface antigen (HBsAg) carrier state can be achieved in about 30% of hepatitis B e antigen (HBeAg)-positive patients and 20% of HBeAg-negative patients. Recent studies have focused on identification of pretreatment and on-treatment factors that allow the selection of patients who are likely to achieve a sustained response to peginterferon therapy in order to avoid the side-effects and costs associated with unnecessary treatment. Future studies need to address whether specific virologic benchmarks can guide individualized decisions concerning therapy continuation and whether peginterferon combined with new potent nucleos(t)ide analogues improves treatment outcomes.

Simultaneous genotyping and quantification of hepatitis B virus for genotypes B and C by real-time PCR assay

Hepatitis B virus (HBV) is an important cause of human chronic liver diseases and is a major public health problem. Viral load and HBV genotype play critical roles in determining clinical outcomes and response to antiviral treatment in hepatitis B patients. Viral genotype detection and quantification assays are currently in use with different levels of effectiveness. In this study, the performance of a real-time genotyping and quantitative PCR (GQ-PCR)-based assay was evaluated. Through the use of genotype-specific primers and probes, this assay provides simultaneous identification and quantification of genotypes B and C in a single reaction. Our GQ-PCR correctly identified all predefined genotypes B and C, and no cross-reaction between genotypes B and C were observed. The GQ-PCR identified more cases of HBV infections with mixed genotypes B and C than direct sequencing did. Samples from 127 HBV-infected Chinese patients were genotyped with GQ-PCR, revealing 56.7% HBV as genotype B, 13.4% as genotype C, and 29.8% as mixed genotypes B and C. This assay provides a reliable, efficient, and cost-effective means for quantification of the B and C genotypes of HBV in single or mixed infections. This assay is suitable for sequential monitoring of viral load levels and for determining the relationship between the genotype viral load and stage of disease in Asians.

Hepatitis B virus genotyping by enzyme-linked immunosorbent assay in Taiwan

PURPOSE

Restriction fragment length polymorphism (RFLP) and enzyme-linked immunosorbent assay (ELISA) with monoclonal antibodies (mAbs) were used in this study to detect genotypes of HBV, and the efficiency and precision of ELISA using the mAbs for HBV genotype detection were also estimated.

METHODS

The ELISA with mAbs method was used for the detection of HBV genotype in a Taiwanese population. The HBV genotypes of 100 chronic hepatitis B patients were determined by ELISA and were then compared with those obtained using RFLP.

RESULTS

Genotype B was found to be the most prevalent in this study (63% by RFLP; 62% by ELISA) followed by genotype C (31% by RFLP; 35% by ELISA). There was no significant difference between the results obtained by RFLP and ELISA (P = 0.75). The ELISA overall genotypeable rate, the correct genotyping rate from genotypeable specimens, and the concordance of the HBV genotyping assay was 96.00, 94.79, and 91.00%; for the ELISA HBV genotyping assay for genotype B specimens was 96.77, 100.00, and 96.77%; and for genotype C specimens was 97.14, 91.18, and 88.57%, respectively. The mean HBV DNA level was higher in the specimens that could be genotyped by both RFLP and ELISA samples (6.24 ± 1.77 vs. 2.34 ± 0.90, log IU/ml), and a significant difference in terms of HBV DNA level of more than 2 × 10(3) IU/ml was identified between the genotyped RFLP samples (P < 0.001).

CONCLUSIONS

ELISA is a practical and a useful method for HBV genotyping in a clinical setting in Taiwan, in particular for patients with lower levels of HBV DNA.

Nucleos(t)ide analogues treatment outcome in genotype B and C chronic hepatitis B

BACKGROUND

Hepatitis B genotypes influence the course and severity of the disease.

AIM

To compare the treatment outcome of chronic hepatitis B genotype B and C patients after treating with nucleos(t)ide analogues for six months.

PATIENTS AND METHODS

Forty chronic hepatitis B patients attending the liver clinic of Hospital for Tropical diseases, Bangkok, were studied in retrospective cohort design. Six genotype B patients (15%) and thirty-four genotype C patients (85%) were treated. Serum hepatitis B viral load, serum alanine amino transferase level, HBeAg status and alpha-feto protein level were measured at the time of starting nucleos(t) analogues therapy, and six months later. Besides, achievement of undetectable viral load was assessed in patients with normal serum alanine amino transferase compared to patients with high serum alanine amino transferase level.

RESULTS

After six months of nucleos (t) analogues treatment, achievement of undetectable hepatitis B viral load was higher in genotype B patients (66.7%) than in genotype C patients (42.4%) (Relative Risk=1.57, 0.79-3.14). Biochemical remission, HBeAg seroconversion and tumor marker levels between the two groups were not significantly different. Moreover, achievement of undetectable hepatitis B viral load was significantly higher in normal alanine amino transferase level (75%) than in patients with high serum alanine amino transferase level (33.3%) on nucleos(t)ide analogue treatment (Relative Risk=2.25, 1.20- 4.20).

CONCLUSION

Chronic hepatitis B treatment outcome between genotype B and C were not significantly different. Patients with normalized serum alanine amino transferase level tend to achieve undetectable viral load after nucleoside analogues treatment.

Clinical relevance and public health significance of hepatitis B virus genomic variations

Ten hepatitis B virus (HBV) genotypes (A-J) and 34 HBV subgenotypes have been identified so far. HBV genotypes and subgenotypes have distinct geographical distributions, and have been shown to differ with regard to clinical outcome, prognosis, and response to interferon treatment. Infection with subgenotype A2 is frequently associated with high viral load, resulting in acute infection via horizontal transmission. Genotypes A and B are more sensitive to interferon treatment than genotypes D and C, respectively. Genotype B is more frequent in acute hepatitis than genotype C, whereas genotype C (C2) is more frequently associated with an increased risk of hepatocellular carcinoma (HCC), mostly cirrhotic, as compared with genotype B (B2). Genotype mixture is associated with high viral load and worse outcome of HBV infection. HBV mutations in the S genes, especially amino acids substitution at position 145 (G145R), are associated with immune escape, whereas mutations in the PreS or S genes which impair HBsAg secretion could present a risk to blood safety. HBV variants harboring mutations in the viral polymerase gene that confer resistance to nucleoside analogs may be selected during antiviral therapy. Different genotypes have distinct mutation patterns in the PreS and EnhII/BCP/Precore regions. PreS deletions, C1653T, T1753V, and A1762T/G1764A are associated with an increased risk of HCC. HCC-associated HBV mutants may not transmit via mother-to-child transmission, and are likely generated during HBV-induced pathogenesis. Examination of HBV mutations alone or in combination and host genetic susceptibility will be helpful in classifying the HBV-infected subjects who will develop HCC and need active anti-viral treatments.

Novel method for genotyping hepatitis B virus on the basis of TaqMan real-time PCR

Chronic infection with hepatitis B virus (HBV) is an important cause of cirrhosis and cancer of the liver. HBV is currently classified into eight genotypes, A to H. Accumulated evidence shows that the genotype influences both the clinical course of infection and the response to treatment. We describe a new method for genotyping based on TaqMan real-time PCR, which identifies all HBV genotypes without post-PCR processing. In this assay, each sample is processed in four multiplex real-time PCRs, each targeting two or three genotype-specific segments of HBV. By analyzing 185 samples representing all genotypes and different proportions of genotype mixtures, we could validate high accuracy of the assay. We conclude that this new assay represents a significant advancement for both diagnostics and clinical research because it is accurate, practical, and based on a technique that is well established in many virological laboratories.

Clinical relevance and public health significance of hepatitis B virus genomic variations

Ten hepatitis B virus (HBV) genotypes (A-J) and 34 HBV subgenotypes have been identified so far. HBV genotypes and subgenotypes have distinct geographical distributions, and have been shown to differ with regard to clinical outcome, prognosis, and response to interferon treatment. Infection with subgenotype A2 is frequently associated with high viral load, resulting in acute infection via horizontal transmission. Genotypes A and B are more sensitive to interferon treatment than genotypes D and C, respectively. Genotype B is more frequent in acute hepatitis than genotype C, whereas genotype C (C2) is more frequently associated with an increased risk of hepatocellular carcinoma (HCC), mostly cirrhotic, as compared with genotype B (B2). Genotype mixture is associated with high viral load and worse outcome of HBV infection. HBV mutations in the S genes, especially amino acids substitution at position 145 (G145R), are associated with immune escape, whereas mutations in the PreS or S genes which impair HBsAg secretion could present a risk to blood safety. HBV variants harboring mutations in the viral polymerase gene that confer resistance to nucleoside analogs may be selected during antiviral therapy. Different genotypes have distinct mutation patterns in the PreS and EnhII/BCP/Precore regions. PreS deletions, C1653T, T1753V, and A1762T/G1764A are associated with an increased risk of HCC. HCC-associated HBV mutants may not transmit via mother-to-child transmission, and are likely generated during HBV-induced pathogenesis. Examination of HBV mutations alone or in combination and host genetic susceptibility will be helpful in classifying the HBV-infected subjects who will develop HCC and need active anti-viral treatments.

HBV and HCV therapy

One year of interferon therapy inhibits HBV replication in one third of the patients whereas long-term administration of oral nucleos(t)ide analogues is efficient in most of them, as long as early treatment adaptation in patients with partial virological response and resistance is provided. Following the demonstration of a more potent antiviral effect in terms of sustained virological response (SVR) rates, Pegylated-IFN coupled with Ribavirin has become the standard treatment for chronic hepatitis C, with nearly 65% of all treated patients achieving a SVR. Long-term suppression of HBV and eradication of HCV would halt the progression of chronic hepatitis to cirrhosis, hepatocellular carcinoma and liver decompensation.

Baseline predictors of virological response for chronic hepatitis B patients

AIM: To determine which baseline factors of chronic hepatitis B patients are predictive of virological response to Peginterferon α-2b therapy.

METHODS: A total of 21 HBeAg-positive chronic hepatitis B (CHB) patients treated with Peginterferon α-2b were recruited. They were treated with Peginterferon α-2b (0.5-1.0 μg/kg per week) for 24 wk and followed up for 24 wk. Clinical and laboratory data of the patients were determined at pretreatment and at week 12, at 24 during treatment, and at week 48 during follow up.

RESULTS: Ten patients achieved a virological response at the end of treatment. Their baseline serum alanine aminotransferase (ALT), thyroid-stimulating hormone (TSH), and total thyroxin (TT4) levels were significantly different from those who failed treatment. The positive predictive values (PPV) and negative predictive values (NPV) of ALT, TSH, and TT4 were 75% and 89 %, 75% and 89 %, and 75% and 75%, respectively. Moreover, combinations of the baseline ALT and TT4, ALT and TSH, TT4 and TSH levels had much higher PPV and NPV (86% and 88%, 89% and 100%, 83% and 100%, respectively).

CONCLUSION: Baseline serum ALT, TSH, and TT4 levels, especially in combination, have high predictive values of virological response to Peginterferon α-2b in HBeAg-positive CHB patients.

Meta-analysis: the effect of interferon on development of hepatocellular carcinoma in patients with chronic hepatitis B virus infection

PURPOSE

In patients chronically infected with hepatitis B virus, interferon has been used for the purpose of viral suppression by loss of hepatitis B e antigen (HBeAg) with or without seroconversion to antibody to HBeAg (anti-HBe). However, discussion about the effect of interferon on the development of hepatocellular carcinoma (HCC) has been controversial.

METHODS

We conducted a meta-analysis of published studies. Eight studies were retrieved (1,303 patients), including two randomized controlled trials (RCTs) and six non-RCTs (553 patients received interferon treatment).

RESULTS

The pooled estimate of the preventive effect of treatment was significantly in favor of interferon (risk difference -5.0%; 95% CI -9.4 to -0.5, P = 0.028). By subgroup analyses, the preventive effect of interferon treatment was shown in the Asian population (risk difference -8.5%; 95%CI -13.6 to -3.6, P = 0.0012), the population with the incidental rate of HCC >or=10% if untreated with interferon (risk difference -9.4%; 95%CI -14.2 to -4.6, P = 0.0001), and the population with the proportion of HBeAg-positive patients to the study population >or=70% (RD -6.0%; 95%CI -11.8 to -0.2, P = 0.043). However, the preventive effect of interferon was not shown in the European population, the population with a lower incidental rate of HCC if untreated with interferon, and the population with the lower proportion of HBeAg-positive patients to the study population. An evaluation using the Begg method indicated no evidence of publication bias.

CONCLUSIONS

Interferon treatment is considered to restrain HCC development in patients with chronic hepatitis B virus infection, especially in HBeAg-positive Asians.

Association of hepatitis B virus subgenotypes and basal core promoter/precore region variants with the clinical features of patients with acute hepatitis

BACKGROUND

In endemic areas, including Japan, basal core promoter (BCP) and precore (PC) variants of hepatitis B virus (HBV) have been reported to be associated with the clinical outcome of acute hepatitis B patients. However, the associations of BCP/PC variants with clinical outcomes have not been observed in nonendemic areas. HBV subgenotypes, which show geographic variations in prevalence, may underlie this discrepancy in clinical outcomes. Little is known about the differences in the clinical and virological features of HBV subgenotypes and BCP/PC variants. The aim of this study was to investigate the distributions of subgenotypes and BCP/PC variants to identify clinical differences in acute hepatitis B patients.

METHODS

One hundred thirty-nine patients with acute hepatitis were enrolled. Nested polymerase chain reaction was used to amplify the pre-S region of HBV for genotyping and the BCP/PC regions for variant screening.

RESULTS

HBV subgenotypes A1 (n = 3), A2 (n = 28), B1 (n = 3), B2 (n = 9), C1 (n = 5), C2 (n = 84), C variant (n = 1), D2 (n = 3), and H (n = 3) were detected. BCP/PC variants were not associated with progression to chronic hepatitis. Patients infected with subgenotype C2 who progressed to fulminant hepatic failure frequently carried variants at nucleotides non-T1753 and non-T1754 and T1762, A1764, and A1896.

CONCLUSIONS

BCP/PC variants would be associated with progression to fulminant hepatitis in subgenotype C2. Knowledge of HBV subgenotypes and BCP/PC variants is useful for developing strategies to treat acute hepatitis B patients.

Construction and expression of eukaryotic plasmids containing lamivudine-resistant or wild-type strains of Hepatitis B Virus genotype C

AIM: To construct eukaryotic expression plasmids of full-length Hepatitis B Virus (HBV) genotype C genome, which contain lamivudine-resistant mutants (YIDD, YVDD) or wild-type strain (YMDD), and to observe the expression of HBV DNA and antigens [hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg)] of the recombinant plasmids in HepG2 cells.

METHODS: Three HBV full-length genomes were amplified from the plasmids pMD18T-HBV/YIDD, pMD18T-HBV/YVDD and pMD18T-HBV/YMDD, using PCR. Three recombinant plasmids were generated by inserting each of the PCR products into the eukaryotic expression vector pcDNA3.1 (+), between the EcoRI and HindIII sites. After being characterized by restriction endonuclease digestion, and DNA sequence analysis, the recombinant plasmids were transfected into HepG2 cells. At 48 and 72 h post-transfection, the levels of intracellular viral DNA replication were detected by real-time PCR, and the expression of HBsAg and HBeAg in the cell culture supernatant was determined by ELISA.

RESULTS: Restriction endonuclease digestion and DNA sequence analysis confirmed that the three recombinant plasmids were correctly constructed. After transfecting the plasmids into HepG2 cells, high levels of intracellular viral DNA replication were observed, and HBsAg and HBeAg were secreted into the cell culture supernatant.

CONCLUSION: Eukaryotic expression plasmids pcDNA3.1 (+)-HBV/YIDD, pcDNA3.1 (+)-HBV/YVDD or pcDNA3.1 (+)-HBV/YMDD, which contained HBV genotype C full-length genome, were successfully constructed. After transfection into HepG2 cells, the recombinant plasmids efficiently expressed HBV DNA, HBsAg and HBeAg. Our results provide an experimental basis for the further study of HBV lamivudine-resistant mutants.

Current antiviral therapies for chronic hepatitis B

Among current treatment options for chronic hepatitis B, nucleoside/nucleotide analog therapy has better tolerability and most patients respond to the therapy, while interferon (IFN) therapy has rather severe side-effects and a lower response rate. However, nucleoside/nucleotide analog therapies have problems of the emergence of drug resistance and poor sustainability of response after discontinuation. After the first nucleoside/nucleotide analog lamivudine, adefovir and entecavir are now utilized in many countries. Adefovir has efficacy for lamivudine resistant patients and current data suggests that adding adefovir to ongoing lamivudine is better than switching to adefovir in terms of viral suppression and the occurrence of resistance. Entecavir can be the first choice for naïve patients, although cross-resistance has been known for lamivudine resistant patients and mutational screening should take place before using entecavir with such patients. Many other new nucleoside/nucleotide analogs are being developed such as telbivudine, clevudine and tenofovir; the details of each drug will be disclosed in near future.

Understanding the immunopathogenesis of chronic hepatitis B virus: an Asian prospective

The study of hepatitis B virus (HBV) immunity has been mainly focused on understanding the differences between subjects who are able to control HBV infection and patients with persistent infection. These studies have been instrumental in increasing our knowledge on the pathogenesis of the disease caused by HBV. However, it is possible that heterogeneity of host and virus factors which segregate in ethnically distinct HBV infected populations might modify important aspects of the immune response against HBV. In this review, we reexamine the kinetics and the pattern of HBV-specific immunity associated with control or persistence of infection. We then discuss how the epidemiological, genetic and viral characteristics peculiar to Asian patients can impact the profile of HBV-specific immunity.

Demonstration of an association between detection of IgG antibody reactivity towards the C-terminal region of the preS1 protein of hepatitis B virus and the capacity to respond to interferon therapy in chronic hepatitis B

BACKGROUND AND AIM

The treatment of hepatitis B virus (HBV) remains complex, with somewhat unpredictable responses. The aim of this study was to determine the predictive value of the pretreatment presence of circulatory antibodies towards a synthetic peptide mimicking the amino acids 94-117 of the preS1 protein of HBV and the capacity to respond to alpha-inteferon (IFN-alpha) treatment.

METHODS

The anti preS1(94-117) antibodies were measured by a peptide-based enzyme-linked immunosorbent assay (ELISA) and the response to INF-alpha therapy was judged by the effect on the viral kinetics as measured by an assay based on quantitative polymerase chain reaction during the treatment and follow up.

RESULTS

We found a significant (P < 0.001) correlation between the pretreatment presence of anti preS1(94-117) antibodies and a decrease in viral levels on follow up after the end of IFN-alpha therapy. The combined response of HBV DNA suppression (P < 0.001), hepatitis B e antigen (HBeAg) loss (P < 0.0001), anti-HBe seroconversion (P < 0.005) and AST aminotransferase normalization (P < 0.01) was also highly associated with the pretreatment presence of anti preS1(94-117) antibodies.

CONCLUSION

The positive predictive value (PPV) of anti preS1(94-117) in determining a virological response was 83% and the negative predictive value (NPV) was 100%, indicating that in the absence of pretreatment anti preS1 reactivity virtually no patient has the capacity to respond to IFN-alpha therapy. Our findings may help to improve the efficacy of INF-alpha therapy for chronic hepatitis B (CHB) by guiding the selection of patients for treatment and optimizing the clinical management of the individual patient.